Refrigerating apparatus



Aug. 8, 1944. L GIBSON 2,355,289

REFRIGERATING APPARATUS Filed June 30, 1943 XWVEN OR.

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Patented Aug. 8, 1944 REFRIGERATING APPARATUS J. Lowell Gibson, Dayton. Ohio. assignor to General Motors Corporation, Dayton, Ohio, at corporation of Delaware Application June 30, 1943, Serial No. 492,849

6 Claims. (Cl. 62-140) This invention relates to refrigerating apparatus and more particularly to improved apparatus for use in the conditioning of air.

One object of this invention is to provide an improved arrangement for disposing of the moisture removed from the air.

Another object of this invention is to provide an improved arrangementv for separating the lubricant from the refrigerant.

Still another object of this invention is to provide means for cooling the motor compressor unit.

More particularly it is an object of this invention to provide a heat exchange coil disposed in the condensate collecting pan which serves the multiple purposes of evaporating the condensate and removing the superheat from the compressed refrigerant before it is discharged into the motor compressor casing wherein the oil separates out from the refrigerant.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

Fig. 1 is a horizontal sectional view, somewhat diagrammatic, of a window sill type of air conditioning unit incorporating my invention; and

Fig. 2 is a vertical sectional view, largely diagrammatic, showing the refrigerant flow circuit.

One of the big problems in the design of a window sill type of air conditioning unit is that of providing suitable means for disposing of the condensate which collects on the evapo- Another problem is that of providing a simple and inexpensive means for separating the lubricant from the refrigerant discharged from the compressor so as to prevent an excessive amount of lubricant entering the condenser and the evaporator. My improved arrangement helps to solve these and other problems in a practical manner.

In Fig. 1 of the drawing, I have shown somewhat diagrammatically a self contained air conditioning unit of the type adapted to be mounted directly on a window sill with one portion of the unit projecting into the room and another portion of the unit projecting out of the room in accordance with well known practice. Reference numeral ill designates a casing separated into an evaporator compartment l2 and a refrigerant liquefying compartment H by means of a partition i8. An evaporator I8 is disposed adjacent the outlet 20 through which the conditioned air is discharged directly into the space to be conditioned. An inlet opening 22 is provided in the front wall of the evaporator compartment as shown. The air to be conditioned is circulated through the evaporator compartment by means of the fan 24 driven by a motor 26. The direction of air flow is diagrammatically indicated by means of arrows as shown. The condenser'air fan 25 is also driven by the motor 26.

An opening 28 is provided at the rear of the cabinet, the one portion of which serves as an inlet opening and the other portion of which serves as an outlet opening as indicated by the arrows which diagrammatically show the direction of air flow. A condenser 38 is placed adjacent to and is substantially coextensive with the opening 28. A conventional sealed motor compresser unit 32 is disposed within the compartment l4 as shown. The refrigerant vapor leaving the evaporator l8'flows to the inlet of the compressor through the line 34. The compressed superheated refrigerant together with the entrained lubricant is discharged directly to the outside of the motorcompressor casing 38 through the line 40 which leads to the superheat removing coil 42 located in the condensate collecting pan 44. The partially cooled mixtureof compressed refrigerant and lubricant leaves the superheat removing coil thIOlE'h the line 46 which discharges the mixture directly into the upper portion of the motor compressor casing 38. Having been partially cooled the entrained lubricant will tend to separate out from the compressed refrigerant within the motor compressor casing 38. The casing 38 thus serves as a lubricant separating chamber.

The substantially lubricant-free compressed refrigerant leaves the casing 38 through the out- A let line 48 which leads to the condenser 30. The

refrigerant liquefied in the condenser 38 fiows to the evaporator l8 through the line 52 in which is placed a conventional refrigerant flow control element 54. The refrigerant flow control element 54 may be either a thermostatic expansion valve, a fixed restrictor, or any other type of pressure reducing means. The construction of the motor compressor unit has not been shown as this is conventional. The refrigerant lines only have been changed so that the compressed refrigerant leaving the compressor does not discharge directly into the motor compressor housing but is discharged into the superheat removing coil 42, as shown in the drawing, before being discharged into the motor compressor housing.

As shown in the drawing, the condensate collects in the condensate pan 44 in which the superheat removing coil 42 is located. By virtue of this construction the hot compressed gas flowing through the coil 42 causes evaporation of the condensate and the vaporized condensate is picked up by the air flowing in over the one side of the condenser and is discharged to the outside along with the air flowing out over the other side of the condenser. The cooled mixture of refrigerant and lubricant returning to the motor compressor casing 36 from the coil 42 helps to cool the motor compressor mechanism.

There may be some extreme weather'conditions in which the condensate will not readily evaporate. In the event that condensate drains into the pan 44 at a faster rate than it is evaporated therefrom, the excess condensate will overflow into the bottom of the housing l and will drain out through the drain 56. The drain 56 is provided solely as a safety feature and would rarely, if ever,- be used. While I have shown the drain for carrying away the condensate in the event of any overflow, it is obvious that any other well known means for disposing of the excess condensate may be used. The pan 44 has enough capacity to store some of the excess condensate. For purposes of illustration, one condensate pan has been shown whereas two separate pans joined by a pipe could be used as is now common practice.

While I have made use of the main motor compressor casing as the oil separating chamber, it is obvious that the oil may be separated from the refrigerant in some special chamber rovided for the purpose. However, there is a distinct advantage in returning the cooled refrigerant gas and lubricant mixture to the motor compressor casing itself since the cooled mixture serves to cool the motor compressor mechanism.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In a self contained air conditioning unit, a casing, partition means within said casing separating said casing into an evaporator compartment and a condenser compartment, an evaporator within said evaporator compartment, a condenser within said condenser compartment, means for flowing a first stream of air in thermal exchange with said evaporator, means for flowing a second stream of air in thermal exchange with said condenser, means for collecting the condensate separated from the air by said evaporator, a heat exchange coil arranged in thermal exchange relationship with said condensate, a compressor, a casing for said compressor, means for conveying refrigerant vaporized in said evaporator to the inlet of said compressor, means for conveying the compressed refrigerant leaving said compressor into said heat exchange coil, means for conveying the refrigerant leaving said heat exchange coil into said compressor casing, means for conveying the refrigerant leaving said casing to said condenser, and means for conveying refrigerant from said condenser to said evaporator, said last named means including a pressure regulating means.

2. A refrigerating system comprising in com= bination, an evaporator, a condenser, means forming an oil separating chamber, a compressor, means for flowing air in thermal exchange in said evaporator, means for flowing air in thermal exchange with said condenser, means for collecting the condensate separated out from the air by said evaporator, a heat exchange coil arranged in heat exchange relationship with said condensate, means for conveying refrigerant vaporized in said evaporator to the compressor, means for discharging the compressed refrigerant into said heat exchange coil, means for conveying the refrigerant leaving said heat exchange coil into said oil separating chamber, means for conveying the substantially lubricant free refrigerant from said chamber to said condenser, and means for supplying the refrigerant liquefied by said condenser to said evaporator, said last named means including a pressure reducing means.

3. A self contained portable air conditioning unit of the type adapted to be mounted on the window sill of a room to be conditioned comprising in combination, a cabinet, an evaporator in said cabinet, a condenser in said cabinet, means for directing a first stream of air in thermal exchange with said evaporator, means for directing a second stream of air in thermal exchange with said condenser, a condensate collecting receptacle, means for withdrawing refrigerant vapor from said evaporator and discharging compressed refrigerant into said condenser,' said means including an oil separating chamber and including a heat exchange coil arranged in thermal exchange relationship with said condensate and having an outlet into said oil separating chamber.

4. A refrigerating system comprising in combination, an evaporator, a condenser, means forming a compressor chamber, a compressor within said chamber, means for flowing air in thermal exchange with said evaporator, means for flowing air in thermal exchange with said condenser, means for collecting the condensate separated out from the air by said evaporator, a heat exchange coil arranged in heat exchange relationship with said condensate, means for conveying refrigerant vaporized in said evaporator to the compressor, means for discharging the compressed refrigerant into said heat exchange coil, means for conveying the refrigerant leaving said heat exchange coil into said compressor chamber, means for conveying the substantially lubricant free refrigerant from said chamber to said condenser, and means for supplying the refrigerant liquefied by said condenser to said evaporator, said last named means including a pressure reducing means.

5. In combination; means forming a first air flow passage; an evaporator in said first air flow passage; means forming a second air flow passage having an inlet and an outlet; a condenser having a portion adjacent the inlet of said second passage and having another portion adjacent the outlet of said second passage; a condensate collecting receptacle disposed within and intermediate the inlet and the outlet of said second named passage; a refrigerant compressor; a housing for said compressor; refrigerant flow connections between said evaporator, said compressor, said compressor housing, and said condenser; said refrigerant flow connections including'a superheat removing coil disposed within said second named air flow passage receiving compressed refrigerant assumes 3 from said compressor and discharging into said compressor housing; and means for disposing of excess condensate which is not evaporated in said receptacle.

6. A refrigerating system comprising in combination, an evaporator, a condenser, means forming a motor-compressor housing, a motor and a compressor driven by the motor in said housing, means for flowing air in thermal exchange with said evaporator, means for flowing air in thermal exchange with said condenser, means for collecting the condensate separated out from the air by said evaporator, a heat exchange coil arranged in heat exchange relationship with said condensate, means for conveying refrigerant vaporized in said evaporator to the compressor, means for discharging the compressed refrigerant into said 5 heat exchange coil, means for conveying the re- 10 condenser to said evaporator, said last named means including a pressure reducing means.

J. LOWELL GIBSON. 

